//import java.util.Scanner;
//public class Test {
//    public static void main(){
//        Scanner in = new Scanner(System.in);
//        int a = in.nextInt();
//        if(a>=5000){
//            System.out.print((int)(a*0.6));
//        }
//        else if(a>=2000){
//            System.out.print((int)(a*0.7));
//        }
//        else if(a>=500){
//            System.out.print((int)(a*0.8));
//        }
//        else{
//            System.out.print((int)(a*0.9));
//        }
//    }
//}
//import java.util.*;
//        import java.util.Scanner;
//public class Main {
//    public static void main(String[] args){
//        Scanner in = new Scanner(System.in);
//        int a = in.nextInt();
//        if(a>=5000){
//            System.out.print((int)(a*0.6));
//        }
//        else if(a>=2000){
//            System.out.print((int)(a*0.7));
//        }
//        else if(a>=500){
//            System.out.print((int)(a*0.8));
//        }
//        else if(a>=100){
//            System.out.print((int)(a*0.9));
//        }
//        else{
//            System.out.print(a);
//        }
//    }
//}
/*

import java.util.Scanner;
public class Main {
    public static void main(String args[]){
        Scanner sc1 = new Scanner(System.in);
        double a = sc1.nextDouble();
        double b = sc1.nextDouble();
        double c = 0.0;
        c=b/(a*a);
        if(c<18.5){
            System.out.print("偏瘦");
        }
        else if(c>=18.5&&c<20.9){
            System.out.print("苗条");
        }
        else if(c>=20.9&&c<24.9){
            System.out.print("适中");
        }
        else{
            System.out.print("偏胖");
        }
    }
}
*/
/*
import java.util.Scanner;
public class Main {
    public static void main(String agrs[]){
        Scanner sc = new Scanner(System.in);
        String grade = sc.nextLine();
        if(grade.equals("A")){
            System.out.print("优秀");
        }
        else if(grade.equals("B")){
            System.out.print("良好");
        }
        else if(grade.equals("C")){
            System.out.print("及格");
        }
        else if(grade.equals("D")){
            System.out.print("不及格");
        }
        else{
            System.out.print("未知等级");
        }
    }
}*/


import java.util.Scanner;
public class Main {
    public static void main(String[] args) {

        //write your code here........
        long res = 0;
        long add = 1;
        for(int i = 1; i <= 10; i++){
            add *= 10;
            res += add - 1;
        }
        System.out.println(res);
    }
}










